Leadership is a key element of quality management, and, as such, it has been identified as an influential factor in the maturity of quality management systems (QMSs). Some of the previous studies on the relationship between leadership styles and QMS performance have argued that no universal best leadership style exists, stressing that leadership practices should be appropriate to the context. Thus, this research aims to further explore this relationship by considering the QMS context, namely the practitioners' leadership profile and the QMS maturity. Accordingly, the primary objectives of this study are 1) to understand if a leadership style is predominant depending on the QMS maturity and 2) to understand the relationship between the leadership practices of different styles and the dimensions of the QMS maturity. An exploratory quantitative study was developed in companies located in Portugal through a survey based on the maturity model developed by Nascimento et al. (2016) and the Multifactor Leadership Questionnaire®-5X Short Leader Form MLQ of Avolio and Bass (1995). The diagnosis disclosed that only 32% of the sample had a QMS with higher maturity levels (4 and 5, a scale of 1 to 5). The results highlighted that no single leadership style dominates a specific maturity level. Furthermore, a significant positive correlation was demonstrated between several practices of transformational and transactional leadership styles and the dimensions of QMS maturity. As a practical contribution, a guideline was provided with some examples of leadership practices and their impacts on the specific dimensions of QMS maturity. Some steps were also proposed to enable organisations to develop a tailored programme to foster leadership practices suitable to the internal context and promote QMS maturity.